Instant messaging (IM) and chat are forms of real-time communication between two or more users based on typed text. Written communication is conveyed via communication devices such as computers connected over a network such as the Internet. In a chat room, a group of people can type in messages that are seen by everyone in the “room.” Instant messages are usually between two people.
Current instant messaging services rely on a text window with a scrollbar. The communication proceeds with one's message just below, or above, the previous one, in a two dimensional (2D) visualization. Each message is identified by an image or a nickname of its speaker, eventually also informing the time of speaking (writing). In order to see previous communication, the user must scroll up or down the window. It is also difficult to easily see one's speech separated from the other's speech. It is also difficult to determine instances of the string of communication.